Does credit card debt lead to depression?

Credit cards can carry more than high interest rates—they actually might increase your chances of depression.

It's common sense that high levels of debt can stress you out. Now researchers have found a statistically significant link between short-term household debt, such as credit card debt and overdue bills, and increases in symptoms of depression. (The math is complicated but those interested can read more here).

The link between depression and debt was strongest among unmarried people, people near retirement and those who are less educated, according to the new study by researchers at the University of Wisconsin-Madison. The study also found that, on average, people's depressive symptoms tend to increase as their short-term debt rises. (Tweet This.)

"Our results suggest that taking on unsecured debt may adversely influence psychological well-being," said Lawrence Berger, the study's lead author and director of the University of Wisconsin-Madison's Institute for Research on Poverty.

Of course, Berger stresses that the research deals in averages, not individuals. The data can't tell if any particular person who maxes out their credit cards will be prone to depression. In other words, correlation doesn't prove causation.

The study found no link between depression symptoms and mid- and long-term debt. Berger hypothesizes that these types of debt are "experienced more positively, as investments in the future, whereas short-term debt may be a source of stress or psychological angst."

But researchers didn't look at behavior during the Great Recession. They analyzed data from the National Survey of Families and Households conducted six years apart and ending in 1994.

They noted that the data were "collected long before the recessions of 2001 or 2008, the housing boom and bust, or significant increases in student debt that marked the last decade. It is quite possible that mortgage debt, especially in areas with declining home values, is perceived differently now than in the past, which may suggest a differential pattern of association with depressive symptoms."

The study echoes other research that has found a link between high debt and poor mental health. People in debt are three times more likely to have a mental health problem than those not in debt, according to a 2013 meta-analysis of 65 academic papers by researchers from the University of Southampton and Kingston University in the U.K.

"This research shows a strong relationship between debt and mental health; however it is hard to say which causes which at this stage," said Thomas Richardson, a University of Southampton clinical psychologist who led the analysis, in a statement at the time the research was released.

"It might be that debt leads to worse mental health due to the stress it causes. It may also be that those with mental health problems are more prone to debt because of other factors, such as erratic employment."